This section provides background information related to the present disclosure which is not necessarily prior art.
A frangible projectile is a projectile that disintegrates upon impacting a target to minimize its travel. Frangible projectiles are most commonly used in shooting ranges, because they are less likely to pass through the intended target or ricochet. However, frangible projectiles are also used in other, non-training applications, for example in situations where there is heightened concern about damage to property or injury to persons adjacent the intended target. For example, some frangible projectiles will disintegrate upon striking wallboard, making it less likely that a shot will damage property or injure persons in adjacent rooms.
Frangible projectiles preferably can be fired from conventional weapons, and thus preferably have physical and ballistic properties comparable to conventional projectiles.
There are competing considerations in designing a frangible projectile that is of reasonable cost, that can be reliably fired, and yet which breaks up as intended upon striking its intended target. Many attempts have been made to provide such projectiles, including U.S. Pat. No. 7,685,942 on Frangible Powdered Iron Projectiles; U.S. Pat. No. 7,555,987 on Frangible Powered Iron Projectiles; U.S. Pat. No. 7,380,503 Method And Apparatus For Self-Destruct Frangible Projectiles; U.S. Pat. Nos. 7,322,297 and 7,143,679 Cannelured Frangible Projectile And Method Of Canneluring A Frangible Projectile; U.S. Pat. No. 6,892,647 Lead Free Powdered Metal Projectiles; U.S. Pat. No. 6,799,518 Method And Apparatus For Frangible Projectiles; U.S. Pat. No. 6,694,888 Frangible Bullet; U.S. Pat. No. 6,691,623 Frangible Powdered Iron Projectiles; U.S. Pat. No. 6,536,352 Lead-free Frangible Bullets And Process For Making Same; U.S. Pat. No. 6,263,798 Frangible Metal Bullets, Ammunition And Method Of Making Such Articles; U.S. Pat. No. 6,257,149 Lead-free Bullet; U.S. Pat. No. 6,240,850 Bullets For Use In Hitting Targets At Short Range; U.S. Pat. No. 6,115,894 Process Of Making Obstacle Piercing Frangible Bullet; U.S. Pat. No. 6,090,178 Frangible Metal Bullets, Ammunition And Method Of Making Such Articles; U.S. Pat. No. 6,074,454 Lead-free Frangible Bullets And Process For Making Same; U.S. Pat. No. 5,917,143 Frangible Powdered Iron Projectiles; U.S. Pat. No. 5,894,645 Method Of Forming A Non-Toxic Frangible Bullet Core; U.S. Pat. No. 5,852,858 Non-toxic Frangible Bullet; U.S. Pat. No. 5,852,255 Non-toxic Frangible Bullet Core; U.S. Pat. No. 5,763,819 Obstacle Piercing Frangible Bullet; U.S. Pat. No. 5,679,920 Non-toxic Frangible Bullet; U.S. Pat. No. 5,665,808 Low Toxicity Composite Bullet And Material Therefore; and U.S. Pat. No. 5,616,642 Lead-free Frangible Ammunition, the disclosures of which is incorporated herein by reference.